Instead of configuring the PopUP on a click or mouse hoover for every layer in Flex Viewer, there should be a widget to create PopUP from the layer's properties such as HTML Popup, MapTip or Identify that are already set in MapDocument / Layer Property. I have over 100 GIS layers in my .mxd and configuring a Popup for each at the Flex environment is very time consuming. All the layers properties such as simbology, scale dependencies, label, etc. are automatically carried from ArcMap to Flex application, how come the maptip, HTML popup or identify is not carried over?
